A solution of the strong CP problem via the Peccei-Quinn mechanism through the Nieh-Yan modified gravity and cosmological implications

Journal Article · Tue Jun 15 00:00:00 EDT 2010 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.81.125015· OSTI ID:21408108

Lattanzi, Massimiliano ^[1]; Mercuri, Simone ^[2]

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1. ICRA and Dipartimento di Fisica, Universita di Roma 'Sapienza', Piazzale Aldo Moro 2, 00185 Roma (Italy)
2. Institute for Gravitation and the Cosmos, Pennsylvania State University, 104 Davey Lab, Physics Department, University Park, Pennsylvania 16802 (United States)

By identifying the recently introduced Barbero-Immirzi field with the QCD axion, the strong CP problem can be solved through the Peccei-Quinn mechanism. A specific energy scale for the Peccei-Quinn symmetry breaking is naturally predicted by this model. This provides a complete dynamical setting to evaluate the contribution of such an axion to the cold dark matter content of the Universe. Furthermore, a tight upper bound on the tensor-to-scalar ratio production of primordial gravitational waves can be fixed, representing a strong experimental test for this model.

• OSTI ID: 21408108
• Journal Information: Physical Review. D, Particles Fields, Vol. 81, Issue 12; Other Information: DOI: 10.1103/PhysRevD.81.125015; (c) 2010 The American Physical Society; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
CP INVARIANCE
GRAVITATION
GRAVITATIONAL WAVES
MATHEMATICAL SOLUTIONS
NONLUMINOUS MATTER
QUANTUM CHROMODYNAMICS
SYMMETRY BREAKING
UNIVERSE
FIELD THEORIES
INVARIANCE PRINCIPLES
MATTER
QUANTUM FIELD THEORY